Cooling systems for cooling electric machines within electrified vehicles

Abstract

This disclosure details cooling systems for cooling electric components, such as electric machines, within electrified vehicles. Exemplary cooling systems may include a spray bar positioned relative to a rear face of a stator of the electric machine. In some embodiments, the spray bar may be positioned axially between the rear face of the stator and a torque converter housing. One or more nozzles of the spray bar are configured to direct a coolant between adjacent back irons of the stator, onto end windings of the stator, or both. Actively cooling the stator allows the electric machine to operate at higher torques and speeds, thereby increasing performance.

What is claimed is: 
     
       1. A transmission system, comprising:
 an electric machine including a rotor and a stator; 
 a spray bar positioned adjacent to a face of the stator; and 
 a first nozzle of the spray bar configured to direct a coolant between adjacent back irons of the stator. 
 
     
     
       2. The transmission system as recited in  claim 1 , wherein the spray bar is positioned axially between a rear face of stator and a torque converter of the transmission system. 
     
     
       3. The transmission system as recited in  claim 2 , wherein the spray bar is located near a top edge of the stator that coincides with a twelve o'clock position of the stator in its mounted position within the transmission system. 
     
     
       4. The transmission system as recited in  claim 1 , wherein the spray bar includes a crescent shaped body. 
     
     
       5. The transmission system as recited in  claim 1 , wherein the spray bar covers between 60 degrees and 180 degrees of the face of stator. 
     
     
       6. The transmission system as recited in  claim 1 , wherein the first nozzle is configured to direct the coolant between the adjacent back irons of the stator, and comprising a second nozzle configured to direct the coolant onto end windings of the stator. 
     
     
       7. The transmission system as recited in  claim 6 , wherein the first nozzle includes a first orifice having a first diameter and the second nozzle includes a second orifice having a second diameter, wherein the first diameter is larger than the second diameter. 
     
     
       8. The transmission system as recited in  claim 1 , wherein the spray bar is directly attached to a face of the stator. 
     
     
       9. The transmission system as recited in  claim 1 , wherein the spray bar is suspended within an open space defined between a rear face of the stator and a torque converter housing. 
     
     
       10. A transmission system, comprising:
 an electric machine including a rotor and a stator; 
 a spray bar positioned adjacent to a rear face of the stator; and 
 a first nozzle of the spray bar configured to direct a coolant between adjacent back irons of the stator, onto end windings of the stator, or both, 
 wherein the spray bar is directly attached to the rear face of the stator, 
 wherein the spray bar includes a piloting surface received within a groove of the stator. 
 
     
     
       11. An electrified vehicle, comprising:
 a front module at least partially housing an electric machine; 
 a transmission gearbox aft of the front module; 
 a torque converter located axially between the front module and the transmission gearbox; and 
 a spray bar positioned axially between a rear face of a stator of the electric machine and a housing of the torque converter, 
 wherein the spray bar includes a piloting surface received within a groove formed in the face of the stator or is suspended within an open space defined between the face of the stator and a housing of the torque converter. 
 
     
     
       12. The electrified vehicle as recited in  claim 11 , comprising a feed tube connected to the front module by a first mounting attachment and connected to the spray bar by a second mounting attachment. 
     
     
       13. The electrified vehicle as recited in  claim 12 , wherein the feed tube is in fluid communication with a coolant passage formed in the front module at the first mounting attachment and is in fluid communication with a hollow section of the spray bar at the second mounting attachment. 
     
     
       14. The electrified vehicle as recited in  claim 11 , wherein the spray bar includes a crescent shaped body. 
     
     
       15. The electrified vehicle as recited in  claim 11 , wherein the spray bar covers between 60 degrees and 180 degrees of the rear face of stator. 
     
     
       16. The electrified vehicle as recited in  claim 11 , wherein the spray bar is located near a top edge of the stator, and the top edge coincides with a twelve o'clock position of the stator. 
     
     
       17. The electrified vehicle as recited in  claim 11 , wherein the spray bar includes a plurality of nozzles that protrude from a front face of the spray bar. 
     
     
       18. The electrified vehicle as recited in  claim 17 , wherein a first portion of the plurality of nozzles is configured to direct a coolant between adjacent back irons of the stator and a second portion of the plurality of nozzles is configured to direct the coolant onto end windings of the stator. 
     
     
       19. The electrified vehicle as recited in  claim 18 , wherein the first portion of the plurality of nozzles includes a first orifice having a first diameter and the second portion of the plurality of nozzles includes a second orifice having a second diameter, wherein the first diameter is larger than the second diameter. 
     
     
       20. The electrified vehicle as recited in  claim 11 , wherein the spray bar is positioned relative to a top edge of the stator but not relative to a bottom edge of the stator.